Mount Prospect, Illinois 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

517
FXUS63 KLOT 310743
AFDLOT

Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
243 AM CDT Sun May 31 2026

.KEY MESSAGES...

- A slight chance for some pockets of very light rain or
  sprinkles late this evening and tonight.

- Generally dry conditions expected through much of the upcoming
  work week with the next appreciable rain chances not until
  Friday into next weekend.

&&

.DISCUSSION...
Issued at 243 AM CDT Sun May 31 2026

Today`s weather should be very similar to yesterday`s. After
starting the day in the 50s, afternoon temperatures will warm
into the 80s around most inland areas with 60s and lower 70s
anticipated around Lake Michigan. High pressure centered out to
our east will provide light easterly winds today with a breezier
push anticipated behind an inland-moving lake breeze during the
latter part of the day. We`ll see a fair mix of clouds and blue
sky, although cloud cover will be thickening up later in the
day.

Later this morning, a weak shortwave impulse will eject east
out of the central Plains and work across the region tonight
atop a building southern stream ridge. This wave will shunt a
deep baroclinic zone east into our vicinity and provide an
opportunity for some light rain late today into tomorrow. Some
guidance is resolving light simulated radar returns in our west
as early as this afternoon as the wave begins advancing across
the Mississippi. However, a great deal of dry air through the
lower part of the column and a general lack of forcing should
make precip development difficult to achieve prior to dusk.

The late evening and overnight period appears to harbor the
greatest precip potential when we`ll find the deepest layer
saturation with the baroclinic zone overhead and seemingly
greatest forcing with the primary vort lobe associated with this
wave working across. Guidance varies between a dry forecast and
a decent concentration of true light showers, and the
discrepancies boil down to the strength of the wave and the
amount of low level dry air to eat away at precip. At this
point, the most likely scenario appears to be isolated instances
of very light rain or sprinkles through the night, although a
few, more appreciable showers can`t be ruled out. There is some
support for additional precip during the day on Monday as the
baroclinic zone gets hung up in the vicinity. Guidance favors
even more dry air feeding in after daybreak and a continued lack
of forcing, so not anticipating any precip beyond early morning
at this point.

The blocking upper air pattern responsible for the quiet
weather these past several days will begin breaking down over
the Hudson Bay today. It will slowly shear out across the Great
Lakes through Thursday and park another prominent surface high
over the region during the middle part of the week. This should
keep any mid-week rain chances at bay while afternoon
temperatures continue hitting the upper 70s and 80s. Late this
week after the high finally pushes off the east coast, a
synoptic system is favored to move across the region and bring a
chance for some rain on Friday, the best chance that we see
over the next week. Ahead of the wave, a warmer air mass will
advect into the region. There`s a good amount of spread in
temperature guidance for late week, but support is there for
near 90 degree temps Thursday and Friday.

Doom

&&

.AVIATION /06Z TAFS THROUGH 12Z MONDAY/...
Issued at 1222 AM CDT Sun May 31 2026

There are no significant aviation weather concerns. Winds will
be predominantly southeasterly this morning but will shift out
of the northeast during the afternoon behind a lake breeze.
There is a chance for some sprinkles overnight into Monday
morning, but have left a mention out at this time due to the
generally small chances and low operational impacts.

Carlaw

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...None.
IN...None.
LM...None.

&&

$$

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